"Gold," BBC World Service Documentary, August 12, 2009.

  "An Academic View Of The Right To Party," Talk Of The Nation, NPR, January 10, 2007.

  "'Ambassadors,' Tracing The History Of Diplomacy," Talk Of The Nation, NPR, July 26, 2006.

  "Richard Tarnas," Tapestry, March 19, 2005.

  "Zero," In Our Time, BBC Radio 4, May 13, 2004.

  "The Alphabet," In Our Time, BBC Radio 4, December 18, 2003.

  "Doubt: A History," Talk Of The Nation, NPR, November 13, 2003.

  "Nature," In Our Time, BBC Radio 4, July 10, 2003.

  "Blood," In Our Time, BBC Radio 4, May 22, 2003.